Telomeres are located at the end of chromosomes. They are known to protect chromosomes and prevent cellular senescence. Telomere length shortening has been considered an important marker of aging. Many studies have reported this concept in connection with neurodegenerative disorders. Considering the role of telomeres, it seems that longer telomeres are beneficial while shorter telomeres are detrimental in preventing neurodegenerative disorders. However, several studies have shown that people with longer telomeres might also be vulnerable to neurodegenerative disorders. Before these conflicting results can be explained through large-scale longitudinal clinical studies on the role of telomere length in neurodegenerative disorders, it would be beneficial to simultaneously review these opposing results. Understanding these conflicting results might help us plan future studies to reveal the role of telomere length in neurodegenerative disorders. In this review, these contradictory findings are thoroughly discussed, with the aim to better understand the role of telomere length in neurodegenerative disorders.
Background and purpose: We investigated existing nonpharmacological programs for people with dementia (PWD) to explore critical factors related to the effectiveness of these types of programs.
Methods: We conducted a qualitative systematic literature review to identify nonpharmacological intervention programs developed for PWD and reviewed 36 randomized controlled trials. Among several outcomes reported in each study, we focused on the most common outcomes including quality of life (QoL), neuropsychiatric symptoms, depression, agitation, and cognition for further review.
Results: Several factors were identified that might affect the outcomes of nonpharmacological interventions for PWD including study design, characteristics of the intervention, maintaining research participants, heterogeneity issues, and implementation fidelity. About half of studies in this review reported positive program effects on their targeted outcomes such as Well-being and Health for PWD on improving quality of life, neuropsychiatric symptoms and agitation; cognitive stimulation therapy on QoL, neuropsychiatric symptoms and cognition; and a stepwise multicomponent intervention on neuropsychiatric symptoms, depression and agitation.
Conclusions: We found some programs even with a rigorous study design did not produce expected outcomes while other programs with poor designs reported positive outcomes, which necessitates further investigation on the validity of the assessments. Factors such as individual tailored and customized interventions, promoting social interactions, ease of administration and compatibility of interventions, and developing program theory need to be considered when developing nonpharmacological intervention programs.
Background and purpose: Verbal and nonverbal fluency tests are the conventional methods for examining executive function in the elderly population. However, differences in impairments result in fluency tests in patients with mild cognitive impairments (MCIs) and Alzheimer's disease (AD) and in neural correlates underlying the tests still necessitate concrete evidence.
Methods: We compared the test performances in 27 normal controls, 28 patients with MCI, and 20 with AD, and investigated morphological changes in association with the test performances using structural magnetic imaging.
Results: Patients with AD performed poorly across all the fluency tests, and a receiver operating characteristics curve analysis revealed that only category fluency test discriminated all the 3 groups. Association, category, and design fluency tests involved temporal and frontal regions, while letter fluency involved the cerebellum and caudate.
Conclusions: Category fluency is a reliable measure for screening patients with AD and MCI, and this efficacy might be related to morphological correlates that underlie semantic and executive processing.
Background and purpose: In this study we aimed to find the association between neuropsychological performance and body mass index (BMI) in patients with mild cognitive impairment (MCI). In addition, we investigated the effects of the apolipoprotein E (APOE) genotype in the relationship between the BMI and cognition in MCI.
Methods: We enrolled a cohort of 3,038 subjects with MCI aged 65-90 from the Clinical Research Center for Dementia of South Korea and a dementia cohort of the Ewha Womans University Mokdong Hospital. MCI patients were classified into three subgroups according to the Asian standard of BMI. We compared cognitive performances between groups by one-way analysis of variance. To investigate the effects of the APOE genotype, we used multivariate linear regression models after adjusting for possible confounders.
Results: Even though normal BMI groups were younger, had more females, and had less comorbidities, the higher BMI groups had better cognitive functions. Among subjects with APOE ε4 carriers, there was a positive relationship between the BMI and the memory task alone.
Conclusions: Our findings suggested that higher BMI in patients with MCI were associated with better cognitive performance. The effects of the APOE ε4 genotype in the associations between BMI and cognition were distinguishing. Therefore, according to physical status, APOE ε4 genotype-specific strategies in the assessments and treatments may be necessary in elderly patients with MCI.